You just have to:
- Search for "X-plane to GPS" app in the Play Store.
- Download it.
- Follow instructions to get GPS signal from X-Plane.
- Run Air Navigation Pro.
Here's a link to the page of "X-Plane to GPS" App:
https://play.google.com/store/apps/details?id=com.appropel.xplanegps
iOS version
In order to connect Air Navigation Pro to the X-Plane Flight Simulator, a special plugin must be installed in the «plugin» folder of X-Plane.